Software Defined Radio

Software Defined Radio devices, often abbreviated as SDR, is a radio communication system where components that have been traditionally implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer.

In short SDR is a programmable radio-receiver which you can connect to your PC. Software on your PC tunes it, and processes/receives/reads the radio-data.

There are numerous cheap USB-dongles which you can buy for approximately €10, and the one I purchased looks like this:

The USB-device identifies itself as follows when inserted into my desktop:

I was later informed, via private email, that librtlsdr0 installs a suitable collection of udev-rules that include my device.

I can confirm that restarting udev, and removing + re-inserting the radio-receiver allows me to run the dump1090 command as my regular-user, without the need for sudo.

Decoding Radio Transmissions

A lot of cheap hardware uses Radio transmissions at 433Mhz, for example the "home automation" kits that consist of a small remote control that will allow you to turn on/off electrical outlets, and a large number of wireless temperature sensors.

I took advantage of this myself in my Smart Alarm Button-project, because there is a great piece of software which allows decoding a lot of protocols and devices.